Display apparatus having inorganic insulating layers with contact holes and grooves

ABSTRACT

A display apparatus may include a substrate having a first bending area between a first area and a second area, the first bending area to be bent with a first bending axis that extends along a first direction, as a center; a first inorganic insulating layer on the substrate and having a first opening corresponding to the first bending area; a first organic material layer filling at least a portion of the first opening; and a first conductive layer that extends from the first area to the second area through the first bending area and is on the first organic material layer. The first organic material layer may have a concavo-convex surface at least in a portion of an upper surface thereof. At least a portion of the first conductive layer may extend along a third direction forming an angle of about 0° to about 90° with the first direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a continuation application based on currently pending U.S.patent application Ser. No. 16/417,011 (now U.S. Pat. No. 10,797,252),filed May 20, 2019, the disclosure of which is incorporated herein byreference in its entirety. U.S. patent application Ser. No. 16/417,011is a continuation application of U.S. patent application Ser. No.15/342,248, filed Nov. 3, 2016 (now U.S. Pat. No. 10,297,771), issuedMay 21, 2019, the disclosure of which is incorporated herein byreference in its entirety. U.S. Pat. No. 10,297,771 claims prioritybenefit, under 35 U.S.C. § 119, of Korean Patent Application No.10-2016-0053548, filed on Apr. 29, 2016, in the Korean IntellectualProperty Office, the disclosure of which is incorporated herein byreference for all purposes.

BACKGROUND 1. Field

One or more embodiments relate to a display apparatus, and moreparticularly, to the display apparatus which may assure a long usagelife, while defects may be reduced.

2. Description of the Related Art

In general, a display apparatus has a display unit on a substrate.Visibility from various angles may be improved or an area of anon-display region may be reduced, by bending a portion of the displayapparatus.

However, problems are generated in conventional display apparatuses thatdefects occur during a manufacturing process of a bent display apparatusor a usage life thereof is reduced.

SUMMARY

In accordance with one or more embodiments, a display apparatus mayinclude a substrate having a first bending area between a first area anda second area, the first bending area to be bent with a first bendingaxis that extends along a first direction, as a center; a firstinorganic insulating layer on the substrate and having a first openingcorresponding to the first bending area; a first organic material layerfilling at least a portion of the first opening; and a first conductivelayer that extends from the first area to the second area through thefirst bending area and is on the first organic material layer. The firstorganic material layer may have a concavo-convex surface at least in aportion of an upper surface thereof. At least a portion of the firstconductive layer may extend along a third direction forming an angle ofabout 0° to about 90° with the first direction.

According to an embodiment, at least a portion of the first conductivelayer may be extended along the third direction in the first bendingarea.

According to an embodiment, the third direction may form an angle ofabout 45° with the first direction, and at least a portion of the firstconductive layer may form an angle of about 45° with the first bendingaxis.

According to an embodiment, the third direction may form an angle ofabout 90° with the first direction, and at least a portion of the firstconductive layer may be arranged perpendicular to the first bendingaxis.

According to an embodiment, at least a portion of the first conductivelayer may be arranged in parallel with the first bending axis.

According to an embodiment, an area of the first opening may be largerthan that of the first bending area.

According to an embodiment, the first organic material layer may havethe concavo-convex surface only in the first opening.

According to an embodiment, a shape of an upper surface of the firstconductive layer on the first organic material layer may correspond tothat of an upper surface of the first organic material layer.

According to an embodiment, the concavo-convex surface may have aplurality of protrusion axes extended along a fourth direction formingan angle of about 0° to about 90° with the first direction.

According to an embodiment, the concavo-convex surface may include aplurality of protruded areas which are respectively formed with theplurality of protrusion axes as centers, in a fifth directionperpendicular to the fourth direction.

According to an embodiment, a distance between a central portion of thefirst opening and the plurality of protrusion axes may be shorter thanthat between another portion in the first opening and the plurality ofprotrusion axes.

According to an embodiment, heights from an upper surface of thesubstrate to the plurality of protruded areas, at the central portion ofthe first opening may be greater than those from the upper surface ofthe substrate to the plurality of protruded areas, at another portion ofthe first opening.

According to an embodiment, the display apparatus may further include asecond organic material layer on the first conductive layer and fillingat least a portion of the first opening.

According to an embodiment, the second organic material layer mayinclude a concavo-convex surface at least at a portion of an uppersurface thereof.

According to an embodiment, the second organic material layer mayinclude the concavo-convex surface only in the first opening.

According to an embodiment, a shape of the concavo-convex surface on theupper surface of the second organic material layer may correspond tothat of the concavo-convex surface on the upper surface of the firstorganic material layer.

According to an embodiment, the first conductive layer may include afirst surface facing the substrate at least at a portion thereof, asecond surface which is an opposite surface to the first surface, and atleast one hole penetrating from the first surface to the second surface.

According to an embodiment, the first conductive layer may include thehole only in the first opening.

According to an embodiment, the first conductive layer may include thehole, only at locations corresponding to the first bending area.

According to an embodiment, the display apparatus may further include astress neutralization layer arranged over the first conductive layer andthe stress neutralization layer may include an organic material.

According to an embodiment, the display apparatus may include a thinfilm transistor in the first area or the second area, the thin filmtransistor having a source electrode, a drain electrode, and a gateelectrode; and an encapsulation layer that covers a display device inthe first area.

According to an embodiment, the display apparatus may further include asecond conductive layer in the first area or the second area, the secondconductive layer being on a layer different from the first conductivelayer, and is electrically connected to the first conductive layer.

According to an embodiment, an elongation percentage of the firstconductive layer may be larger than that of the second conductive layer.

BRIEF DESCRIPTION OF THE DRAWINGS

Features will become apparent to those of skill in the art by describingin detail exemplary embodiments with reference to the attached drawingsin which:

FIG. 1 illustrates a perspective view of a display apparatus accordingto one or more embodiments;

FIG. 2 illustrates a cross-sectional view of a portion of the displayapparatus of FIG. 1 ;

FIG. 3A illustrates a plan view of a first conductive layer arranged ina second area, a first bending area, and a first area according to anembodiment;

FIG. 3B illustrates a plan view of a first conductive layer arranged inthe second area, the first bending area, and the first area according toanother embodiment;

FIG. 3C illustrates a plan view of a first conductive layer arranged inthe second area, the first bending area, and the first area according toanother embodiment;

FIG. 4 illustrates a plan view of a first conductive layer arranged inthe second area, the first bending area, and the first area according toanother embodiment;

FIG. 5 illustrates a plan view of a first conductive layer arranged inthe second area, the first bending area, and the first area according toanother embodiment;

FIG. 6A illustrates a plan view of a first conductive layer arranged inthe second area, the first bending area, and the first area according toanother embodiment;

FIG. 6B illustrates a cross-sectional view of FIG. 6A taken along a lineVI-VI′;

FIG. 7 illustrates a cross-sectional view of a portion of a displayapparatus according to a comparative example;

FIG. 8 illustrates a cross-sectional view of a portion of a displayapparatus, in detail, around a first opening of a first inorganicinsulating layer according to another embodiment;

FIG. 9 illustrates a cross-sectional view of a portion of a displayapparatus, in detail, around the first opening of the first inorganicinsulating layer according to another embodiment;

FIG. 10 illustrates a plan view of a first conductive layer and aplurality of protrusion axes which are arranged in the first area, thefirst bending area, and the second area according to an embodiment;

FIG. 11 illustrates a plan view of a first conductive layer and aplurality of protrusion axes which are arranged in the first area, thefirst bending area, and the second area according to another embodiment;

FIG. 12 illustrates a plan view of a first conductive layer and aplurality of protrusion axes which are arranged in the first area, thefirst bending area, and the second area according to another embodiment;

FIG. 13 illustrates a plan view of a first conductive layer and aplurality of protrusion axes which are arranged in the first area, thefirst bending area, and the second area according to another embodiment;

FIG. 14 illustrates a cross-sectional view of a portion of a displayapparatus according to another embodiment;

FIG. 15 illustrates a cross-sectional view of a portion of a displayapparatus according to another embodiment;

FIG. 16 illustrates a cross-sectional view of a portion of a displayapparatus according to another embodiment;

FIG. 17 illustrates a cross-sectional view of a portion of a displayapparatus according to another embodiment;

FIG. 18 illustrates a perspective view of a portion of a displayapparatus according to another embodiment;

FIG. 19 illustrates a plan view of a portion of the display apparatus ofFIG. 18 ;

FIG. 20 illustrates a perspective view of a portion of a displayapparatus according to another embodiment; and

FIG. 21 illustrates a perspective view of a portion of a displayapparatus according to another embodiment.

DETAILED DESCRIPTION

Example embodiments will now be described more fully hereinafter withreference to the accompanying drawings; however, they may be embodied indifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey exemplary implementations to those skilled in the art.

In the drawing figures, the dimensions of layers and regions may beexaggerated for clarity of illustration. It will also be understood thatwhen a layer or element is referred to as being “on” another layer orsubstrate, it can be directly on the other layer or substrate, orintervening layers may also be present. Further, it will be understoodthat when a layer is referred to as being “under” another layer, it canbe directly under, and one or more intervening layers may also bepresent. In addition, it will also be understood that when a layer isreferred to as being “between” two layers, it can be the only layerbetween the two layers, or one or more intervening layers may also bepresent. Like reference numerals refer to like elements throughout.

In the following examples, the x-axis, the y-axis and the z-axis are notlimited to three axes of the rectangular coordinate system, and may beinterpreted in a broader sense. For example, the x-axis, the y-axis, andthe z-axis may be perpendicular to one another, or may representdifferent directions that are not perpendicular to one another

FIG. 1 is a perspective view of a display apparatus according to one ormore embodiments, and FIG. 2 is a cross-sectional view of a portion ofthe display apparatus of FIG. 1 . According to an embodiment, a portionof a substrate 100, i.e., a portion of the display apparatus, may have abent shape as illustrated in FIG. 1 . However, the display apparatus isillustrated in an un-bent state in FIG. 2 for the ease of illustrationconvenience. For reference, the display apparatus will be illustrated inthe un-bent state for the ease of illustration convenience incross-sectional views and plan views of embodiments to be describedbelow.

As illustrated in FIGS. 1 and 2 , the substrate 100 included in thedisplay apparatus may have a first bending area 1BA which extends alonga first direction (a+y direction) according to an embodiment. The firstbending area 1BA may be between a first area 1A and a second area 2A ina second direction (a +x direction) which is perpendicular to the firstdirection. In addition, the substrate 100 may be bent with a firstbending axis 1BAX, which extends along the first direction (the +ydirection), as a center, as illustrated in FIG. 1 . The substrate 100may include various materials having flexible or bendablecharacteristics, e.g., polymer resins such as polyethersulphone (PES),polyacrylate (PAR), polyetherimide (PEI), polyethylene naphthalate(PEN), polyethylene terephthalate (PET), polyphenylene sulfide (PPS),polyallylate, polyimide (PI), polycarbonate (PC), and cellulose acetatepropionate (CAP).

The first area 1A may include a display area DA. The first area 1A mayinclude a portion of a non-display area outside the display area DA inaddition to the display area DA, as illustrated in FIG. 2 . According toanother embodiment, the second area 2A may also include the display areaDA and/or the non-display area.

As illustrated in FIG. 2 , the display area DA of the substrate 100 mayinclude a display device 300 and a thin film transistor (TFT) 210, towhich the display device 300 is electrically connected. The displaydevice 300 may include an organic light-emitting device (OLED) in thedisplay area DA. A pixel electrode of the OLED maybe electricallyconnected to the TFT 210. A thin film transistor (TFT) may be in aperipheral area PA outside the display area DA of the substrate 100,when needed. The TFT arranged in the peripheral area PA may be, forexample, a portion of a circuit unit to control an electrical signalapplied to the display area DA.

The TFT 210 may include a semiconductor layer 211, a gate electrode 213,a source electrode 215 a, and a drain electrode 215 b, which may includeamorphous silicon, polycrystalline silicon or organic semiconductormaterials. A gate insulating layer 120 may be between the semiconductorlayer 211 and the gate electrode 213. The gate insulating layer 120 mayinclude inorganic materials, e.g., silicon oxide, silicon nitride,and/or silicon oxynitride to secure insulation between the semiconductorlayer 211 and the gate electrode 213. An interlayer insulating layer 130may be arranged on the gate electrode 213, the interlayer insulatinglayer 130 including inorganic materials, e.g., silicon oxide, siliconnitride, and/or silicon oxynitride. The source electrode 215 a and thedrain electrode 215 b may be arranged on the interlayer insulating layer130. Insulating layers including inorganic materials may be formed viachemical vapor deposition (CVD) or atomic layer deposition (ALD). Thismethod may be applied to embodiments and various modifications thereofdescribed below.

A buffer layer 110 may be between the TFT 210 and the substrate 100 in astructure described above. The buffer layer 110 may include inorganicmaterials, e.g., silicon oxide, silicon nitride, and/or siliconoxynitride. The buffer layer 110 may increase flatness of an uppersurface of the substrate 100 and/or may prevent or reduce infiltrationof impurities from the substrate 100, etc., to the semiconductor layer211 of the TFT 210. According to another embodiment, the buffer layer110 may include a single layer or two or more layers.

A planarization layer 140 may be arranged on the TFT 210. For example,when the OLED is arranged over the TFT 210, as illustrated in FIG. 2 ,the planarization layer 140 may planarize an upper surface of aprotection layer covering the TFT 210. The planarization layer 140 mayinclude, for example, organic materials, e.g., acryl, benzocyclobutene(BCB), and hexamethyldisiloxane (HMDSO). The planarization layer 140 isillustrated as a single layer in FIG. 2 ; however, the planarizationlayer 140 may be variously modified. For example, the planarizationlayer 140 may have a multi-layer structure. In addition, theplanarization layer 140 may include an opening outside the display areaDA, as illustrated in FIG. 2 , so that a portion of the planarizationlayer 140 in the display area DA and a portion of the planarizationlayer 140 in the second area 2A may be physically separate from eachother. Such arrangement may reduce or prevent impurities from theoutside from reaching the inside of the display area DA through theplanarization layer 140.

The OLED including the pixel electrode 310, a counter electrode 330, andan intermediate layer 320, including a light-emitting layertherebetween, may be arranged on the planarization layer 140, in thedisplay area DA of the substrate 100. The pixel electrode 310 maycontact any one of the source electrode 215 a and the drain electrode215 b, and may be electrically connected to the TFT 210 via an openingformed in the planarization layer 140, etc., as illustrated in FIG. 2 .

A pixel definition layer 150 may be arranged on the planarization layer140. The pixel definition layer 150 may define a pixel by an openingcorresponding to respective sub-pixels, that is, an opening to allow atleast a central portion of the pixel electrode 310 to be exposed. Inaddition, as illustrated in FIG. 2 , the pixel definition layer 150 mayprevent an occurrence of an arc, etc. on edges of the pixel electrode310 by increasing a distance between edges of the pixel electrode 310and the counter electrode 330 over the pixel electrode 310. The pixeldefinition layer 150 may include, for example, organic materials such asPI and HMDSO.

The intermediate layer 320 of the OLED may include low molecular weightmaterials or polymer materials. When the intermediate layer 320 includeslow molecular weight materials, a hole injection layer (HIL), a holetransport layer (HTL), an emission layer (EML), an electron transportlayer (ETL), an electron injection layer (EIL), etc., may have laminatedstructures with a single layer or multiple layers, and include variousorganic materials such as copper phthalocyanine (CuPc),N,N′-Di(naphthalene-1-yl)-N,N′-diphenyl-benzidine (NPB), andtris(8-hydroxyquinoline) aluminum (Alq3). These layers may be formed viaa vacuum deposition method.

When the intermediate layer 320 includes polymer materials, theintermediate layer 320 may have a structure which generally includes anHTL and an EML. In this case, the HTL may include poly3,4-ethylenedioxythiophene (PEDOT) and the light-emitting layer mayinclude high molecular (polymer) materials such aspoly-phenylenevinylene (PPV) and polyfluorene. The intermediate layer320 may be formed via screen printing, inkjet printing, laser inducedthermal imaging (LITI), etc.

However, the intermediate layer 320 is not limited thereto and may havevarious structures. In addition, the intermediate layer 320 may includean integrated layer covering a plurality of pixel electrodes 310 and apatterned layer to correspond to each of the plurality of pixelelectrodes 310.

The common electrode 330 may be arranged in an upper portion of thedisplay area DA and cover the display area DA, as illustrated in FIG. 2. In other words, the common electrode 330 may have an integratedstructure including a plurality of OLEDs and thus, may correspond to theplurality of pixel electrodes 310.

Since the OLED may be easily damaged by humidity, oxygen, etc. from theoutside, an encapsulation layer 400 may protect the OLEDs byencapsulating the OLEDs. The encapsulation layer 400 may cover thedisplay area DA and extend to outside the display area DA. Theencapsulation layer 400 may include a first inorganic encapsulationlayer 410, an organic encapsulation layer 420, and a second inorganicencapsulation layer 430, as illustrated in FIG. 2 .

The first inorganic encapsulation layer 410 may cover the commonelectrode 330, and may include silicon oxide, silicon nitride, and/orsilicon oxynitride, etc. In addition, other layers, e.g., a cappinglayer, may be between the first inorganic encapsulation layer 410 andthe counter electrode 330, when needed. Since the first inorganicencapsulation layer 410 is formed according to a structure thereunder,an upper surface of the first inorganic encapsulation layer 410 may notbe flat. The organic encapsulation layer 420 may cover the firstinorganic encapsulation layer 410 and, unlike the first inorganicencapsulation layer 410, an upper surface thereof may be approximatelyflat. In detail, the upper surface of the organic encapsulation layer420 may be approximately flat in an area corresponding to the displayarea DA. The organic encapsulation layer 420 may include at least onematerial selected from PET, PEN, PC, PI, polyethylene sulfonate (PES),polyoxymethylene (POM), polyallylate, and hexadimethyl siloxane (PDMS).The second inorganic encapsulation layer 430 may cover the organicencapsulation layer 420, and include silicon oxide, silicon nitride,and/or silicon oxynitride, etc. The second inorganic encapsulation layer430 may prevent the organic encapsulation layer 420 from being exposedto the outside by contacting the first inorganic encapsulation layer 410at an edge arranged outside the display area DA.

Since the encapsulation layer 400 includes the first inorganicencapsulation layer 410, the organic encapsulation layer 420, and thesecond encapsulation layer 430, even when cracks occur in theencapsulation layer 400, the cracks may not be extend between the firstinorganic encapsulation layer 410 and the organic encapsulation layer420 or between the organic encapsulation layer 420 and the secondencapsulation layer 430 due to such a multilayer structure. Thus, theformation of an infiltration route of humidity or oxygen from theoutside to the display area DA may be prevented or reduced because ofthis effect.

The buffer layer 110, the gate insulating layer 120, and the interlayerinsulating layer 130, which includes inorganic materials, may becollectively referred to as a first inorganic insulating layer. Thefirst inorganic insulating layer may include a first openingcorresponding to the first bending area 1BA, as illustrated in FIG. 2 .In other words, the buffer layer 110, the gate insulating layer 120, andthe interlayer insulating layer 130 may respectively have openings 110a, 120 a, and 130 a, which correspond to the first bending area 1BA,i.e., overlaps the first bending area 1BA. An area of the first openingmay be greater than that of the first bending area 1BA. As shown in FIG.2 , an opening width (OW) of the first opening is wider than a width ofthe first bending area 1B. The area of the first opening may be definedas the smallest area of the areas of the openings 110 a, 120 a, and 130a of the buffer layer 110, the gate insulating layer 120, and theinterlayer insulating layer 130. For example, in the embodimentillustrated in FIG. 2 , the area of the first opening may be defined asthe area of the opening 110 a of the buffer layer 110 in FIG. 2 .

As illustrated in FIG. 2 , inner side surface of the opening 110 a ofthe buffer layer 110 coincides with an inner side surface of the opening120 a of the gate insulating layer 120, i.e., the inner side surfaces ofthe opening 110 a and the opening 120 a continuously extend along anangle towards the substrate 100. However, embodiments are not limitedthereto.

According to an embodiment, the display apparatus may include a firstorganic material layer 160 filling at least a portion of the firstopening of the first inorganic insulating layer. The first organicmaterial layer 160 is illustrated as filling the whole first opening inFIG. 2 . In addition, the display apparatus may include a firstconductive layer 215 c according to an embodiment. The first conductivelayer 215 c may extend from the first area 1A to the second area 2Athrough the first bending area 1BA, and arranged on the first organicmaterial layer 160. The first conductive layer 215 c may be arranged onan inorganic insulating layer, e.g., the interlayer insulating layer130, where there is no first organic material layer 160. The firstconductive layer 215 c may be simultaneously formed with the sourceelectrode 215 a or the drain electrode 215 b and may be formed of thesame material.

The display apparatus may include second conductive layers 213 a and 213b, in addition to the first conductive layer 215 c. The secondconductive layers 213 a and 213 b may be arranged in the first area 1Aand/or the second area 2A to on a layer different from the layer onwhich the first conductive layer 215 c is arranged, and may beelectrically connected to the first conductive layer 215 c. FIG. 2illustrates that the second conductive layers 213 a and 213 b includethe same material as the gate electrode 213 and are arranged on a samelayer as the gate electrode 213, that is, over the gate insulating layer120. In addition, it is illustrated that the first conductive layer 215c contacts the second conductive layers 213 a and 213 b via contactholes H formed in the interlayer insulating layer 130. It is alsoillustrated that the second conductive layer 213 a is arranged in thefirst area 1A and the second conductive layer 213 b is arranged in thesecond area 2A.

While FIG. 2 illustrates that the second conductive layer 213 b iscovered by the planarization 140, at least a portion of an upper surfaceof the second conductive layer 213 b may not be covered by theplanarization layer 140, etc., but may be exposed to the outside. Thus,the second conductive layer 213 b may be electrically connected tovarious electronic devices, a PCB, etc.

The second conductive layer 213 a arranged in the first area 1A may beelectrically connected to the TFT, etc., in the display area DA, andaccordingly, the first conductive layer 215 c may be electricallyconnected to the TFT, etc., in the display area DA via the secondconductive layer 213 a. The second conductive layer 213 b arranged inthe second area 2A may also be electrically connected to the TFT, etc.,in the display area DA via the first conductive layer 215 c. The secondconductive layers 213 a and 213 b may be electrically connected tocomponents arranged in the display area DA, while being arranged outsidethe display area DA. In addition, the second conductive layers 213 a and213 b may extend along a direction of the display area DA and at least aportion thereof may be arranged in the display area DA, while beingarranged outside the display area DA.

As described above, the display apparatus is illustrated in an un-bentstate in FIG. 2 for the sake of convenience; however, the displayapparatus according to an embodiment is actually in a state in which thesubstrate 100, etc. are bent in the first bending area 1BA, asillustrated in FIG. 1 . In this structure, the substrate 100 of thedisplay apparatus may be manufactured in approximately a flat state in amanufacturing process, as illustrated in FIG. 2 , and thereafter, thedisplay apparatus may be allowed to have a shape as approximatelyillustrated in FIG. 1 by bending the substrate 100, etc. in the firstbending area 1BA. In this case, components arranged in the first bendingarea 1BA may receive the tension stress in a process of bending thesubstrate 100, etc. in the first bending area 1BA.

Accordingly, when the first conductive layer 215 c crossing the firstbending area 1BA, the occurrence of a crack in the first conductivelayer 215 c or defects such as a broken wire in the first conductivelayer 215 c may be reduced or prevented by including a material with ahigh elongation percentage. In addition, an efficiency of electricalsignal transfer in the display apparatus may be enhanced or anoccurrence rate of defects in the manufacturing process may be reduced,by forming the second conductive layers 213 a 213 c in the first area 1Aor the second area 2A with materials which have elongation percentageslower than that of the first conductive layer 215 c, while havingelectrical/physical characteristics different from those of the firstconductive layer 215 c. For example, the second conductive layers 213 aand 213 b may include molybdenum, while the first conductive layer 215 cmay include aluminum. In addition, either the first conductive layer 215c or the second conductive layers 213 a and 213 b may have a multilayerstructure, when needed.

As illustrated in FIG. 2 , the first organic material layer 160 coversan inner side surface of the first opening of the first inorganicinsulating layer. As described above, since the first conductive layer215 c may be simultaneously formed with the source electrode 215 a andthe drain electrode 215 b, with same material, a conductive layer may beformed on the entire surface of the substrate 100. Thereafter, thesource electrode 215 a, the drain electrode 215 b, and the firstconductive layer 215 c may be formed by patterning the conductive layer.When the first organic material layer 160 does not cover the inner sidesurface of the opening 110 a of the buffer layer 110, the inner sidesurface of the opening 120 a of the gate insulating layer 120, and/orthe inner side surface of the opening 130 a of the interlayer insulatinglayer 130, conductive material may not be removed during patterning, butremain on the inner side surface of the opening 110 a of the bufferlayer 110, on the inner side surface of the opening 120 a of the gateinsulating layer 120, and/or on the inner side surface of the opening130 a of the interlayer insulating layer 130. Thus, the remainingconductive material may cause a short between other conductive layers.

Thus, when the first organic material layer 160 is formed, the firstorganic material layer 160 may cover the inner side surface of the firstopening of the first inorganic insulating layer. For reference, thefirst organic material layer 160 is illustrated to have a uniformthickness in FIG. 2 . However, the first organic material layer 160 mayhave a varying thickness depending on locations such that a bendingslope on the upper surface of the first organic material layer 160 maybe smooth on the inner side surface of the opening 110 a of the bufferlayer 110, on the inner side surface of the opening 120 a of the gateinsulating layer 120, and/or around the inner side surface of theopening 130 a of the interlayer insulating layer 130. Accordingly,presence of conductive material which should be removed by patterningmay be effectively reduced or prevented.

As illustrated in FIG. 2 , the first organic material layer 160 mayinclude a concavo-convex surface 160 a at least in a portion of theupper surface (in a +z direction) thereof. Since the first organicmaterial layer 160 includes the concavo-convex surface 160 a, a shape ofthe upper surface and/or the lower surface of the first conductive layer215 c arranged on the first organic material layer 160 may correspond tothat of the concavo-convex surface 160 a of the first organic materiallayer 160.

As described above, the tension stress may be applied to the firstconductive layer 215 c when the substrate 100, etc., are bent in thefirst bending area 1BA in the manufacturing process. Thus, the amount oftension stress applied to the first conductive layer 215 c may bereduced by the upper surface and/or the lower surface of the firstconductive layer 215 c having a shape corresponding to that of theconcavo-convex surface 160 a of the first organic material layer 160. Inother words, the tension stress, which is generated in the bendingprocess, may be reduced via a shape change of the first organic materiallayer 160 with a lower hardness. In this case, the shape of the firstconductive layer 215 c, which has the concavo-convex shape at leastprior to the bending process, may be changed to correspond to the shapeof the first organic material layer 160, which has been changed via thebending. Thus, the occurrence of defects, e.g., a broken wire, in thefirst conductive layer 215 c may be effectively reduced or prevented.

In addition, since the first organic material layer 160 includes aconcavo-convex surface 160 a at least in a portion of the upper surface(in the +z direction) thereof, a surface area of the upper surface ofthe first organic material layer 160 and the surface area of the upperand lower surfaces of the first conductive layer 215 c in the firstopening may be increased. This increase in surface area on the uppersurface of the first organic material layer 160 and the upper and lowersurfaces of the first conductive layer 215 c may provide more room forthe shape change to reduce the tension stress due to the bending of thesubstrate 100, etc.

For reference, since the first conductive layer 215 c is arranged on thefirst organic material layer 160, the lower surface of the firstconductive layer 215 c may have a shape corresponding to that ofconcavo-convex surface 160 a of the first organic material layer 160.However, the upper surface of the first conductive layer 215 c mayinclude its independent concavo-convex surface which does not correspondto the concavo-convex surface 160 a of the first organic material layer160.

For example, the first conductive layer 215 c may be formed by forming aconductive material layer on the first organic material layer 160,doping photoresist on the conductive material layer, varying theexposure amount depending on locations of the photoresist via a slitmask or a half-tone mask, developing the photoresist, etching theexposed conductive material layer, and removing the photoresist. Sincethe exposure amount is different depending on locations of thephotoresist by using the slit mask or the half-tone mask, the level ofetching may be different depending on locations of the conductivematerial layer. In this method, the concavo-convex surface on the uppersurface of the first conductive layer 215 c may be artificially formed.In this case, the upper surface of the first conductive layer 215 c mayinclude its independent concavo-convex surface which does not correspondto the concavo-convex surface 160 a of the first organic material layer160. This effect is applied to embodiments and various modificationsthereof to be described below. Needless to say, even though such processis performed to artificially form the concavo-convex surface on theupper surface of the first conductive layer 215 c, the concavo-convexsurface may be formed to correspond to the concavo-convex surface 160 aof the first organic material layer 160.

According to another embodiment, when the first organic material layer160 is formed, particular portions may be relatively more etched(removed) than other portions, by using the photoresist material, andvarying the exposure amount via the slit mask or the half-tone mask onvarious portions of the upper surface of the first organic materiallayer 160 which are still in approximately a smooth state. In this case,more etched portions may be denoted as concave portions on the uppersurface of the first organic material layer 160. However, themanufacturing method of the display apparatus according to an embodimentis not limited thereto.

As described before, the display apparatus is illustrated as un-bent inFIG. 2 for the sake of convenience; however, the substrate 100 of thedisplay apparatus, etc. may actually be in a bent state in the firstbending area 1BA, as illustrated in FIG. 1 , according to an embodiment.To this effect, the substrate 100 of the display apparatus may bemanufactured in approximately a flat state, as illustrated in FIG. 2 ,in a manufacturing process, and thereafter, the substrate 10, etc. arebent in the first bending area 1BA so that the display apparatusapproximately ends up in a shape as illustrated in FIG. 1 . In thiscase, the first conductive layer 215 c may receive tension stress in aprocess of bending the substrate 100, etc. in the first bending area1BA. However, an occurrence of defects in the first conductive layer 215c in a bending process may be prevented or reduced in the displayapparatus according to an embodiment.

When the first inorganic insulating layer, e.g., the buffer layer 110,the gate insulating layer 120, and/or the interlayer insulating layer130, does not have openings in the first bending area 1BA, but has acontinuous shape from the first area 1A to the second area 2A, and thefirst conductive layer 215 c is arranged on the first inorganicinsulating layer, high tension stress may be applied to the firstconductive layer 215 c in the process of bending the substrate 100, etc.Since the hardness of the first inorganic insulating layer is greaterthan that of the first organic material layer 160, there may be a veryhigh probability that cracks, etc. occur in the first inorganicinsulating layer in the first bending area 1BA. Accordingly, when acrack occurs in the first inorganic insulating layer, there may be avery high probability also that the crack, etc. occur in the firstconductive layer 215 c on the first inorganic insulating layer anddefects, e.g., a broken wire, in the first conductive layer 215 c occur.

However, in the case of the display apparatus according to an embodimentas described above, the first inorganic insulating layer may include thefirst opening in the first bending area 1BA, and a portion of the firstconductive layer 215 c in the first bending area 1BA may be arranged onthe first organic material layer 160, which fills at least a portion ofthe first opening of the first inorganic insulating layer. Since thefirst inorganic insulating layer includes the first opening in the firstbending area 1BA, the probability that cracks, etc., occur in the firstinorganic insulating layer may be extremely low. Further, due tocharacteristics of organic materials used in the first organic materiallayer 160, the probability of cracks occurring therein is low. Thus, theoccurrence of cracks, etc., in the first conductive layer 215 c arrangedon the first organic material layer 160 in the first bending area 1BAmay be reduced or prevented. In addition, since the hardness of thefirst organic material layer 160 is less than that of the firstinorganic insulating layer, the first organic material layer 160 mayabsorb the tension stress caused by bending of the substrate 100, etc.Thus, the concentration of the tension stress in the first conductivelayer 215 c may be effectively reduced.

FIGS. 3A through 3C, 4, and 5 are plan views of the first conductivelayer 215 c arranged in the second area 2A, the first bending area 1BA,and the first area 1A. FIG. 6A is a plan view of the first conductivelayer 215 c arranged in the second area 2A, the first bending area 1BA,and the first area 1A according to another embodiment, and FIG. 6B is across-sectional view of FIG. 6A, taken along a line VI-VI′.

According to one or more embodiments, the display apparatus may includea portion of the first conductive layer 215 c which extends along athird direction (+α direction) forming an angle of about 0° to about 90°with the first direction (the +y direction), as illustrated in FIGS. 3Athrough 3C. Another portion of the first conductive layer 215 c mayextend along the second direction (the +x direction) crossing with thefirst direction (the +y direction). For example, at least a portion ofthe first conductive layer 215 c may extend in the third direction (the+α direction) forming an angle of about 45° with the first direction(the +y direction).

As illustrated in FIG. 3A, the first conductive layer 215 c may extendalong the third direction (the +α direction), only in the first openingof the first inorganic insulating layer. The first conductive layer 215c may extend along the second direction (the +x direction) in areasexcept the first opening.

According to another embodiment, the first conductive layer 215 c mayextend along the third direction (the +α direction), only in the firstbending area 1BA of the first opening, as illustrated in FIG. 3B. Thefirst conductive layer 215 c may extend along the second direction (the+x direction) in areas except the first bending area 1BA, that is, inthe first area 1A and the second area 2A.

According to another embodiment, the first conductive layer 215 c mayextend along the third direction (the +α direction), only in at least aportion of the first bending area 1BA, as illustrated in FIG. 3C.

When the third direction (the +α direction) forms about 0° with thefirst direction (the +y direction), as illustrated in FIG. 4 , the thirddirection (the +α direction) may be the same as the first direction (the+y direction), and at least a portion of the first conductive layer 215c may extend in parallel with the first bending axis 1BAX which extendsalong the first direction (the +y direction).

According to another embodiment, the first conductive layer 215 c mayextend along the third direction (the +α direction) only in the firstbending area 1BA. In other words, the first conductive layer 215 c mayextend in parallel with the first bending axis 1BAX only in the firstbending area 1BA.

When the third direction (the +α direction) forms about 90° with thefirst direction (the +y direction), as illustrated in FIG. 5 , the thirddirection (the +α direction) may be the same as the second direction(the +x direction), and the first conductive layer 215 c may extendalong the second direction (the +x direction) in the first area 1A, thefirst bending area 1BA, and the second area 2A. In other word, at leasta portion of the first conductive layer 215 c may be perpendicular tothe first bending axis 1BAX.

According to an embodiment, as at least a portion of the firstconductive layer 215 c extends along the third direction (the +αdirection) forming an angle of about 0° to about 90° with the firstdirection (the +y direction), at least a portion of the first conductivelayer 215 c may be arranged while forming an predetermined angle withthe first bending axis 1BAX extended along the first direction (the +ydirection).

In addition, since at least a portion of the first conductive layer 215c, which extends along the third direction (the +α direction) whileforming a predetermined angle with the first bending axis 1BAX, isarranged in the first bending area 1BA, the occurrence of cracks, etc.in the first bending area 1BA of the first conductive layer 215 c may beprevented or the probability of cracks occurring may be reduced.

According to an embodiment, the display apparatus may include at leastone hole H in at least a portion of the first conductive layer 215 c, asillustrated in FIG. 6A. An arbitrary number and an arbitrary shape ofthe H in the first conductive layer 215 c are illustrated in FIG. 6A;however, the number and the shape of holes H are not limited thereto.

Referring to FIGS. 6A and 6B, the first conductive layer 215 c mayinclude a first surface 215 c-1 facing the substrate 100, a secondsurface 215 c-2 opposite to the first surface 215 c-1, and a pluralityof holes H penetrating from the first surface 215 c-1 to the secondsurface 215 c-2.

Even though a location of the H in the first conductive layer 215 c isnot limited, the location may be in the first conductive layer 215 c inthe first opening according to another embodiment. In addition,according to another embodiment, the holes H may be arranged in thefirst conductive layer 215 c, only at locations corresponding the firstbending area 1BA in the first opening, as illustrated in FIG. 6B.

When the holes H are arranged in the first conductive layer 215 c atlocations corresponding to the first bending area 1BA, the flexibilityof the first conductive layer 215 c may be improved. In addition,tension stress occurring in the process of bending may be efficientlydistributed. Accordingly, occurrence of cracks in the first conductivelayer 215 c in the first bending area 1BA in the process of bending thesubstrate 100, etc., in the first bending area 1BA may be reduced orprevented.

An embodiment is illustrated in FIG. 6A where a direction along whichthe first conductive layer 215 c extends (the third direction (the +αdirection)) is only perpendicular to the first direction (the +ydirection). However, when the first conductive layer 215 c extends alongthe third direction (the +α direction) forming an predetermined anglewith the first direction (the +y direction), the first conductive layer215 c may include the plurality of holes H, which penetrate from thefirst surface 215 c-1 to the second surface 215 c-2, in a portion of thefirst conductive layer 215 c, regardless of the extension direction.

In addition, when the first conductive layer 215 c extends along thethird direction (the +α direction) forming an predetermined angle withthe first direction (the +y direction), the first conductive layer 215 cmay include holes H only in the first opening or only in the firstbending area 1BA, regardless of the extension direction.

Referring to FIGS. 2 and 5 , the first organic material layer 160 mayinclude a plurality of protrusions on the upper surface (in the +zdirection) to form the concavo-convex surface 160 a on the upper surface(in the +z direction) of the first organic material layer 160. In thiscase, the plurality of protrusions may be respectively formed with aplurality of protrusion axes (GD) which extend along a fourth direction(a +β direction) forming an angle of about 0° to about 90° with thefirst direction (the +y direction) as centers. In other words, theconcavo-convex surface 160 a may include the plurality of protrusions ina fifth direction (a +γ direction) perpendicular to the fourth direction(the +β direction). The protrusion axes described below denote axes onwhich the protrusion centers are arranged, and each of the plurality ofprotrusions may be formed with one protrusion axis as the center. Below,one protrusion axis may be the center of one protrusion. Detaileddescription on the fourth direction (the +β direction) along which theplurality of protrusion axes are extended and the plurality ofprotrusions which are formed with respective protrusion axes as centerswill be provided below.

Referring again to FIG. 2 , the first organic material layer 160 mayinclude the concavo-convex surface 160 a only in the first opening ofthe first inorganic insulating layer. As illustrated in FIG. 2 , thewidth (UEW) of a portion in which the concavo-convex surface 160 a ofthe first organic material layer 160 may be narrower than the width (OW)of the first opening of the first inorganic insulating layer. In theconcavo-convex surface 160 a of the first organic material layer 160, aconcave portion of the concavo-convex surface 160 a may be relativelythinner than a convex portion.

As illustrated in FIG. 7 , according to a comparative example, when theconcavo-convex surface 160 a extends beyond the first opening of thefirst inorganic insulating layer, e.g., is arranged on the inner sidesurface of the opening 110 a of the buffer layer 110, on the inner sidesurface of the opening 120 a of the gate insulating layer 120, and/oraround the inner side surface of the opening 130 a of the interlayerinsulating layer 130, as illustrated in FIG. 7 , the first organicmaterial layer 160 may not be continuously connected, i.e., may bydiscontinuous or broken, e.g., due to the thinner concave portion.Accordingly, this break in the first organic material layer 160 may bereduced or prevented by having the concavo-convex surface 160 a only inthe first opening of the first inorganic insulating layer.

As described above, it is desirable that the first organic materiallayer 160 includes the concavo-convex surface 160 a in the first bendingarea 1BA to prevent the occurrence of a broken wire, etc. of the firstconductive layer 215 c in the first bending area 1BA. Accordingly, thearea of the concavo-convex surface 160 a of the first organic materiallayer 160 may be greater than that of the first bending area 1BA but maybe smaller than that of the first opening. It is illustrated in FIG. 2that the UEW of the portion in which the first organic material layer160 includes the concavo-convex surface 160 a is greater than that ofthe first bending area 1BA and smaller than the OW of the first opening.

The concavo-convex surface 160 a of the upper surface (in the +zdirection) of the first organic material layer 160 may be formed viavarious methods. According to another embodiment, the concavo-convexsurface 160 a may be formed on the upper surface of the first organicmaterial layer 160 via a thermal reflow process. In other words, asmooth concavo-convex surface 160 a may be formed on the upper surfaceof the first organic material layer 160 by depositing organic material,heating and patterning. As the smooth concavo-convex surface 160 a isformed on the upper surface of the first organic material layer 160 viathe thermal reflow process, an advantageous effect may result in thatthe first organic material layer more flexibly absorbs the tensionstress of the first conductive layer 215 c in the bending process. Amethod to form the concavo-convex surface 160 a on the upper surface (inthe +z direction) of the first organic material layer 160 is not limitedthereto, and the concavo-convex surface 160 a may be formed in variousmethods.

FIG. 8 is a cross-sectional view of a portion of the display apparatus,i.e., a detailed cross-sectional view around the first opening of thefirst inorganic insulating layer according to another embodiment. Asnoted above, the concavo-convex surface 160 a of the first organicmaterial layer 160 may include, as described above, the plurality ofprotrusion axes that extend along the fourth direction (the +βdirection) forming an angle of about 0° to about 90° with the firstdirection (the +y direction) and the plurality of protrusions formedwith respective protrusion axes as centers. Here, a distance d1 betweenthe plurality of protrusion axes at the central portion of the firstopening may be shorter than a distance d2 between the plurality ofprotrusion axes in other portions of the first opening.

As described above with reference to FIG. 1 , the substrate 100, etc.,of the display apparatus may be bent with the first bending axis 1BAXwhich extends along the first direction (the +y direction) as the centeraccording to an embodiment. Accordingly, the substrate 100, the firstorganic material layer 160, the first conductive layer 215 c, etc. maybe bent in the first bending area BA1. In this case, the biggest tensionstress may be applied to the central portion of the first bending area1BA, i.e., the central portion of the first opening. Thus, when thedistance d1 between the plurality of protrusion axes at the centralportion of the first opening is shorter than the distance d2 between theplurality of protrusion axes in other portions of the first opening, thesurface area of the upper surface of the first organic material layer160 at the central portion of the first opening and the surface area ofthe upper and lower surfaces of the first conductive layer 215 c at thecentral portion of the first opening may be relatively greater than thesurface area in other portions of the first opening. This indicates thatthe upper surface of the first organic material layer 160 and on theupper and lower surfaces of the first conductive layer 215 c may havemore room for the shape change to reduce the tension stress due to thebending of the substrate 100, etc. A location on which distances betweenthe plurality of protrusion axes change from the distance d1 to thedistance d2 may be in the first bending area 1BA.

Distances between the plurality of protrusion axes may be different fromthe distance d1 or the distance d2 at the central portion of the firstopening or at other portions not adjacent to edges in the first opening.In addition, the distances between the plurality of protrusion axes mayprogressively increase as the locations thereof move from the centralportion of the first opening toward edges of the first opening. Thiseffect may be applied to embodiments and various modifications thereofto be described below.

FIG. 9 is a cross-sectional view of a portion of the display apparatus,i.e., a detailed cross-sectional view around the first opening of thefirst inorganic insulating layer according to another embodiment. Asshown therein, the concavo-convex surface 160 a of the first organicmaterial layer 160 may include, as described above, the plurality ofprotrusion axes that extend along the fourth direction (the +βdirection) forming an angle of about 0° to about 90° with the firstdirection (the +y direction) and the plurality of protrusions formedwith respective protrusion axes as centers. In this case, a height h1from the upper surface of the substrate 100 to the plurality ofprotrusions at the central portion of the first opening may be greaterthan a height h2 from the upper surface of the substrate 100 to theplurality of protrusions at other portions of the first opening.

As described above with reference to FIG. 1 , the substrate 100, etc.,of the display apparatus may be bent with the first bending axis 1BAXwhich extends along the first direction (the +y direction) as the centeraccording to an embodiment. Accordingly, the substrate 100, the firstorganic material layer 160, and the first conductive layer 215 c, etc.may be bent in the BA. In this case, the biggest tension stress may beapplied to the central portion of the first bending area 1BA, that is,the central portion of the first opening. Thus, the surface area of theupper surface of the first organic material layer 160 at the centralportion of the first opening and the surface area of the upper and lowersurfaces of the first conductive layer 215 c at the central portion ofthe first opening may be relatively greater than the surface area inother portions of the first opening, by forming the height h1 from theupper surface of the substrate 100 to the plurality of protrusions atthe central portion of the first opening be greater than the height h2from the upper surface of the substrate 100 to the plurality ofprotrusions at other portions of the first opening. This indicates thatthe upper surface of the first organic material layer 160 and on theupper and lower surfaces of the first conductive layer 215 c may havemore room for the shape change to reduce the tension stress due to thebending of the substrate 100, etc. A location on which the heights fromthe upper surface of the substrate 100 to the plurality of protrusionschange from the height h1 to the height h2 may be in the first bendingarea 1BA.

The heights from the upper surface of the substrate 100 to the pluralityof protrusions may be different from the height h1 or the height h2 atthe central portion of the first opening or at other portions notadjacent to edges in the first opening. In addition, the heights fromthe upper surface of the substrate 100 to the plurality of protrusionsmay decrease as the locations thereof move from the central portion ofthe first opening toward edges of the first opening. This effect may beapplied to embodiments and various modifications thereof to be describedbelow.

FIGS. 10 through 12 are plan views of the first conductive layer 215 cand the plurality of protrusion axes GD arranged in the second area 2A,the first bending area 1BA, and the first area 1A. Below, directionsalong which the first bending axis 1BAX, the first conductive layer 215c, and the protrusion axes GD will be described with reference to FIGS.2, 5, and 10 through 12 .

As described above, the concavo-convex surface 160 a on the uppersurface (in the +z direction) of the first organic material layer 160may be have the UEW, which is wider than the first bending area 1BA, butnarrower than that of the first opening. The concavo-convex surface 160a may include the plurality of protrusions which are formed with theplurality of protrusion axes GD as centers, and the plurality ofprotrusion axes GD may extend along the fourth direction (the +βdirection) forming an angle of about 0° to about 90° with the firstdirection (the +y direction). Accordingly, the concavo-convex surface160 a may include the plurality of protrusions in the fifth direction(the +γ direction) perpendicular to the fourth direction (the +βdirection).

As illustrated in FIG. 5 , the first conductive layer 215 c may extendalong the third direction (the +α direction) forming an angle of about90° with the first direction (the +y direction), and the plurality ofprotrusion axes GD may extend along the fourth direction (the +βdirection) forming an angle of about 0° with the first direction (the +ydirection). In other words, the first conductive layer 215 c may extendalong a direction perpendicular to the first bending axis 1BAX, and theplurality of protrusion axes GD may extend in a direction in parallelwith the first bending axis 1BAX. In addition, the concavo-convexsurface 160 a may include the plurality of protrusions formed with theplurality of protrusion axes GD as centers, in the fifth direction (the+γ direction) perpendicular to the fourth direction (the +β direction).

As a result, according to an embodiment, the plurality of protrusionaxes GD may be formed in a direction perpendicular to the firstconductive layer 215 c, and the concavo-convex surface 160 a may includethe plurality of protrusions formed with the plurality of protrusionaxes GD as centers in a direction in parallel with the first conductivelayer 215 c.

As illustrated in FIG. 10 , the first conductive layer 215 c may extendalong the third direction (the +α direction) forming an angle of about90° with to the first direction (the +y direction), and the plurality ofprotrusion axes GD may extend along the fourth direction (the +βdirection) forming a predetermined angle (for example, about +45°) withthe first direction (the +y direction). In other words, the firstconductive layer 215 c may extend along a direction perpendicular to thefirst bending axis 1BAX, and the plurality of protrusion axes GD may beformed with an inclination of an predetermined angle (for example, about+45°) with the first conductive layer 215 c. In this case, theconcavo-convex surface 160 a may include the plurality of protrusionsformed with the plurality of protrusion axes GD along the fifthdirection (the +γ direction) perpendicular to the fourth direction (the+β direction) along which the plurality of protrusion axes GD areextended as illustrated in FIG. 10 .

As illustrated in FIG. 11 , at least a portion of the first conductivelayer 215 c may extend along the third direction (the +α direction)forming an predetermined angle (for example, about +45°) with the firstdirection (the +y direction), and the plurality of protrusion axes GDmay extend along the fourth direction (the +β direction) forming anangle of about 90° with the first direction (the +y direction).

According to another embodiment, the first conductive layer 215 c mayextend along the third direction (the +a direction) in the first bendingarea 1BA, and the plurality of protrusion axes GD may be arranged with acertain angle from the first conductive layer 215 c in a portion inwhich the first conductive layer 215 c extends along the third direction(the +α direction). The portion in which the first conductive layer 215c extends along the third direction (the +α direction) is not limitedthereto, and the first conductive layer 215 c may extend along the thirddirection (the +α direction) within the UEW.

As illustrated in FIG. 12 , at least a portion of the first conductivelayer 215 c may extend along the third direction (the +α direction)forming an angle of about 0° with the first direction (the +ydirection), and the plurality of protrusion axes GD may extend along thefourth direction (the +β direction) forming an angle of about 90° withthe first direction (the +y direction). In other words, at least aportion of the first conductive layer 215 c may extend parallel with thefirst direction (the +y direction), and the plurality of protrusion axesGD may extend perpendicular to the first direction (the +y direction).As a result, the plurality of protrusion axes GD may be formed in adirection perpendicular to at least a portion of the first conductivelayer 215 c, and the concavo-convex surface 160 a may include theplurality of protrusions formed with the plurality of protrusion axes GDas centers along the fifth direction (the +γ direction) in parallel withthe first direction (the +y direction).

According to an embodiment, the display apparatus may include at least aportion of the first conductive layer 215 c extends in the first bendingarea 1BA along the third direction (the +α direction) forming an angleof about 0° to about 90° with the first direction (the +y direction)along which the first bending axis 1BAX extends. Thus, a contact areabetween the lower surface of the first conductive layer 215 c and thefirst organic material layer 160 may be increased, which may reduce orprevent cracks in the first conductive layer 215 c from being formed dueto the bending process.

In addition, the first conductive layer 215 c may extend along the thirddirection (the +α direction) and the plurality of protrusion axes GDforming the concavo-convex surface 160 a may extended along the fourthdirection (the +β direction) forming an angle of about 0° to about 90°with the first direction (the +y direction). Thus, the tension stressapplied to the first conductive layer 215 c during the bending may beefficiently reduced. In addition to embodiments described above, thedisplay apparatus may include a first direction along which the firstbending axis 1BAX extends as a negative y direction (a −y direction)forming an angle of about 180° with the first direction (the +ydirection). In other words, since the first direction is a directionalong which the first bending axis 1BAX extends, the first direction mayinclude not only the first direction (the +y direction) described above,but also the −y direction forming an angle of about 180° with the firstdirection (the +y direction).

Thus, according to another example, at least a portion of the firstconductive layer 215 c may extend along the third direction (the +αdirection) forming an angle of about 0° to about 90° with the firstdirection (the −y direction) along which the first bending axis 1BAXextends. According to another example, the plurality of protrusion axesGD forming the concavo-convex surface 160 a may also be extended alongthe fourth direction (the +β direction) forming an angle of about 0° toabout 90° with the first direction (the −y direction).

As illustrated in FIG. 13 , the display apparatus according to anembodiment may include at least a portion of the first conductive layer215 c extending in the first bending area 1BA along the third direction(the +α direction) forming an angle of about 45° with the firstdirection (the −y direction) along which the first bending axis 1BAXextends. In addition, the plurality of protrusion axes GD forming theconcavo-convex surface 160 a may extend along the fourth direction (the+β direction) forming an angle of about 45° with the first direction(the +y direction).

FIG. 14 is a cross-sectional view of a portion of the display apparatusaccording to another embodiment. Like reference numbers denote likecomponents in FIG. 14 , as in FIG. 2 , and duplicate descriptions willbe omitted for the sake of simplicity.

As illustrated in FIG. 14 , regarding the area of the first openingformed on the first inorganic insulating layer, the area of the opening120 a of the gate insulating layer 120 may be greater than that of theopening 110 a of the buffer layer 110. In this case, the area of thefirst opening may be defined as the area of the opening with thesmallest area among the openings 110 a, 120 a, and 130 a of the bufferlayer 110, the gate insulating layer 120, and the interlayer insulatinglayer 130, respectively, i.e., that of the opening 110 a.

According to another example, the first opening of the first inorganicinsulating layer may not completely penetrate through in a verticaldirection at the location corresponding to the first bending area 1BA,and the buffer layer 110 may be continuously formed through the firstarea 1A, the first bending area 1BA, and the second area 2A. In otherwords, the buffer layer 110 may be continuously formed, and the gateinsulating layer 120 and the interlayer insulating layer 130 only mayrespectively include the opening 120 a in the first bending area 1BA andthe opening 130 a corresponding to the first bending area 1BA.

The first inorganic insulating layer may include the first opening withvarious configurations different from this configuration. In otherwords, various modifications may be possible such that a portion only ofthe upper surface (in the +z direction) of the buffer layer 110 isremoved, or the first opening is formed while the bottom surface (a −zdirection) of the gate insulating layer 120 is not removed, i.e.,remains.

FIG. 15 is a cross-sectional view of a portion of a display apparatusaccording to another embodiment. Like reference numbers denote likecomponents in FIG. 15 , as in FIG. 2 , and duplicate descriptions willbe omitted for the sake of simplicity. According to an embodiment, thedisplay apparatus may include a second organic material layer 170 priorto an arrangement of the planarization layer 140 on the first conductivelayer 215 c.

According to another embodiment, the second organic material layer 170may completely cover the first conductive layer 215 c with either thesame material as or a different material from the first organic materiallayer 160. In addition, the second organic material layer 170 maycompletely cover the first opening, like the first organic materiallayer 160. However, the embodiments are not limited thereto and thesecond organic material layer 170 may be formed in the first opening orat a location corresponding to the first bending area 1BA only.

The second organic material layer 170 may have a low probability of thecrack occurrence due to characteristics of an organic material usedtherein. Accordingly, the occurrence of cracks, etc., in a portion ofthe first bending area 1BA of the first conductive layer 215 c that isbetween the first organic material layer 160 and the second organicmaterial layer 170 during the bending process may be reduced orprevented.

In addition, since the hardness of the second organic material layer 170is less than that of the inorganic material layer, the second organicmaterial layer 170 and the first organic material layer 160 may absorbthe tension stress caused by the bending of the substrate 100, etc., andthe concentration of the tension stress onto the first conductive layer215 c may be effectively reduced.

FIG. 16 is a cross-sectional view of a portion of a display apparatusaccording to another embodiment. Like reference numbers denote likecomponents in FIG. 16 , as in FIG. 2 , and duplicate descriptions willbe omitted for the sake of simplicity. As illustrated in FIG. 16 , thesecond organic material layer 170 may be arranged prior to thearrangement of the planarization layer 140 on the first conductive layer215 c, and the second organic material layer 170 may include aconcavo-convex surface 170 a on at least a portion of the upper surface(in the +z direction) thereof.

According to another embodiment, the concavo-convex surface 170 a maycorrespond to at least the first bending area 1BA, and may have a largerarea than the first bending area 1BA. According to another embodiment,the concavo-convex surface 170 a of the second organic material layer170 may have a shape corresponding to that of the concavo-convex surface160 a of the first organic material layer 160. However, this is oneembodiment only, and the concavo-convex surface 170 a of the secondorganic material layer 170 may be formed in various shapes, regardlessof the shape of the concavo-convex surface 160 a of the first organicmaterial layer 160. In other words, the concavo-convex surface 170 a ofthe second organic material layer 170 may be formed in a different cyclefrom that of the concavo-convex surface 160 a of the first organicmaterial layer 160, and the concavo-convex surface 170 a of the secondorganic material layer 170 may approximately correspond to theconcavo-convex surface 160 a of the first organic material layer 160.

As described above, according to an embodiment, since the first organicmaterial layer 160 and the second organic material layer 170 arerespectively arranged on the bottom surface and the upper surface of thefirst conductive layer 215 c, and the second organic material layer 170and the first organic material layer 160 absorb the tension stresscaused by the bending of the substrate 100, etc., as a result, theconcentration of the tension stress onto the first conductive layer 215c may be effectively reduced.

In addition, as illustrated in FIG. 16 , since the concavo-convexsurface 170 a of the second organic material layer 170 is formed in ashape corresponding to that of the concavo-convex surface 160 a of thefirst organic material layer 160 on the upper surface of the secondorganic material layer 170, the tension stress is applied to the firstconductive layer 215 c in the first bending area 1BA in the bendingprocess of the substrate 100, etc., may be reduced. Thus, the occurrenceof defects in the first conductive layer 215 c may be prevented orreduced.

The second organic material layer 170 may include a plurality ofprotrusions on the upper surface (in the +z direction) thereof to havethe concavo-convex surface 170 a. In this case, the plurality ofprotrusions may be formed with a plurality of protrusion axes, which areextended along a sixth direction (a +δ direction) forming an angle ofabout 0° to about 90° with the first direction (the +y direction), ascenters. In other words, the concavo-convex surface 170 a may includethe plurality of protrusions in a direction perpendicular to the sixthdirection (the +δ direction).

Even though the sixth direction (the +δ direction) is not illustrated ina drawing, the sixth direction (the +δ direction) may be anpredetermined direction forming an angle of about 0° to about 90° withthe first direction (the +y direction), and may be the same as ordifferent from the fourth direction (the +β direction), along which theprotrusion axes extend, on the concavo-convex surface 160 a of the firstorganic material layer 160.

In other words, the direction (the fourth direction (the +β direction))along which the plurality of protrusion axes are formed on theconcavo-convex surface 160 a of the first organic material layer 160 maybe the same as or different from the direction (the sixth direction (the+δ direction)) along which the plurality of protrusion axes are formedon the concavo-convex surface 170 a of the first organic material layer170.

According to an embodiment, the second organic material layer 170including the concavo-convex surface 170 a of the display apparatus maybe formed with organic materials via various methods.

According to another embodiment, the concavo-convex surface 170 a of maybe formed on the upper surface of the second organic material layer 170by using the same organic material as the concavo-convex surface 160 aof the first organic material layer 160, and the thermal reflow process.In other words, a smooth concavo-convex surface 170 a may be formed onthe upper surface of the second organic material layer 170 by depositingthe photoresist material, heating, and patterning.

According to another embodiment, the plurality of protrusions may beformed on the upper surface of the second organic material layer 170 byapplying the organic material via an inkjet printing method, a jettingmethod, a dotting method, etc., and by hardening via an irradiation ofultra-violet rays.

According to an embodiment, the display apparatus may include theplurality of protrusion axes extending along various directions, thefirst organic material layer 160 and the second organic material layer170 including the plurality of protrusions formed with the plurality ofprotrusion axes as centers, and the first conductive layer 215 c thatextends along various directions. Thus, the tension stress caused by thebending may be distributed and as a result, the concentration of thetension stress may be effectively reduced.

FIG. 17 is a cross-sectional view of a portion of a display apparatusaccording to another embodiment. Like reference numbers denote likecomponents in FIG. 17 , as in FIGS. 2 and 5 , and duplicate descriptionswill be omitted for the sake of simplicity.

According to an embodiment, the display apparatus may include apolarizing plate 520 arranged on an encapsulating layer 400 via anoptically clear adhesive (OCA) 510. The polarizing plate 520 may reducea reflection of outside light. For example, when the outside lighttransmitted through the polarizing plate 520 is reflected on an uppersurface of the counter electrode 330 and passes through the polarizingplate 520 again, a phase of the outside light may be changed due topassing through the polarizing plate 520 for two times. As a result, thephase of the reflected light may become different from that of theoutside light entering the polarizing plate 520, resulting indestructive interference. Thus, the reflection of the outside light maybe reduced and a visibility may be improved.

The OCA 510 and the polarizing plate 520 may cover, for example, theopening of the planarization layer 140, as illustrated in FIG. 15 . Thedisplay apparatus according to an embodiment may not necessarily includethe polarizing plate all the time, and the polarizing plate 520 may beomitted or replaced by other components when needed. For example, theoutside reflection may be reduced by omitting the polarizing plate 520,and using a black matrix and a color filter.

A stress neutralization layer (SNL) 600 may be arranged outside thedisplay area DA. In other words, the SNL 600 may be arranged on thefirst conductive layer 215 c at least to correspond to the first bendingarea 1BA.

When a laminated structure is bent, a stress neutral plane may existinside the laminated structure. If the SNL 600 is omitted, an excessivetension stress, etc., may be applied to the first conductive layer 215 cin the first bending area 1BA due to the bending of the substrate 100,etc., because the location of the first conductive layer 215 c may notcorrespond to that of the stress neutral plane. However, the location ofthe stress neutral plane may be adjusted in the laminated structure,which includes all of the substrate 100, the first conductive layer 215c, the SNL 600, etc. by controlling characteristics of the SNL 600,e.g., a thickness, an elastic modulus, etc., thereof. Accordingly, thetension stress applied to the first conductive layer 215 c may bereduced by arranging the stress neutral plane be arranged around thefirst conductive layer 215 c via the SNL 600.

The SNL 600 may extend to ends of the edges of the substrate 100 of thedisplay apparatus. For example, in the second area 2A, the firstconductive layer 215 c, the second conductive layers 213 a and 213 band/or other conductive layers electrically connected therefrom, etc.may, without having at least a portion thereof be covered by theinterlayer insulating layer 130, the planarization layer 140, etc., beelectrically connected to various electronic devices, printed circuitboards, etc. Accordingly, the first conductive layer 215 c, the secondconductive layers 213 a and 213 b and/or other conductive layerselectrically connected therefrom may have portions which areelectrically connected to various electronic devices, printed circuitboards, etc., each other. In this case, electrically connected portionsneed to be protected from impurities such as outside moisture, and theSNL 600 may serve as a protection layer by having such electricallyconnected portions covered by the SNL 600. For this purpose, the SNL 600may extend, for example, to ends of the edges of the substrate 100 ofthe display apparatus.

The upper surface of the SNL 600 in a direction of the display area DA(a −x direction) is illustrated as to coincide with the upper surface ofthe polarizing plate 520 (in the +z direction) in FIG. 17 ; however,embodiments are not limited thereto. For example, the edge of the SNL600 in the direction of the display area DA (the −x direction) may covera portion of the upper surface at the edge of the polarizing plate 520.Alternatively, the edge of the SNL 600 in the direction of the displayarea DA (the −x direction) may not contact the polarizing plate 520and/or the OCA 510. Especially, in the latter case, a movement of a gas,which is generated in the SNL 600 during or after the forming of the SNL600 in the direction of the display area DA (the −x direction), may beprevented from causing a deterioration of the display devices such asthe OLED and etc.

When the upper surface of the SNL 600 in the direction of the displayarea DA (the −x direction) coincides with the upper surface of thepolarizing plate 520 (the +z direction) as illustrated in FIG. 17 , theedge of the SNL 600 covers a portion of the upper surface at the edge ofthe polarizing plate 520, or the edge of the SNL 600 in the direction ofthe display area DA (the −x direction) contacts the OCA 510, a thicknessof the portion of the SNL 600 closer to the display area DA (the −xdirection) may be greater than that of the other portion of the SNL 600.When forming the SNL 600, a material in a liquid or paste type may bedoped and hardened. A volume of the SNL 600 may be reduced in ahardening process. In this case, when the portion of the SNL 600 closerto the display area DA (the −x direction) contacts the polarizing plate520 and/or the OCA 510, the location of the corresponding portion of theSNL 600 may become fixed. Thus, a volume reduction may occur in theremaining portion of the SNL 600 that is greater than that where the SNL600 contacts the polarizing plate 520 and/or the OCA 510. As a result,the thickness of the portion of the SNL 600 closer to the display areaDA (the −x direction) may be greater than that of the other portion ofthe SNL 600.

FIG. 18 is a perspective view of a portion of a display apparatus, indetail, the substrate 100 according to another embodiment and FIG. 19 isa plan view of a shape of the substrate 100 in FIG. 17 before bending.

Unlike as illustrated in FIG. 1 , the display apparatus according to anembodiment may include a second bending area 2BA, in addition to thefirst bending area 1BA. The 2BA may be arranged in the first area 1A.The substrate 100 may be bent with a second bending axis 2BAX, whichextends along the second direction (the +x direction), as a center inthe same manner as that the substrate 100 is bent with the first bendingaxis 1BAX, which extends in the first direction (the +y direction), asthe center. In this case, the substrate 100 may include a chamferedportion CP due to a chamfering at an edge which is closest to a pointwhere the first bending axis 1BAX and the second bending axis 2BAX crosseach other. Due to presence of the chamfered portion CP, the substrate100 may be simultaneously bent along the first bending axis 1BAX and thesecond bending axis 2BAX crossing therewith as centers.

A radius of curvature R1 in the first bending area may be smaller thanthe radius of curvature R2 in the second bending area 2BA. This effectmay be interpreted as that the bending in the second bending area 2BA issmoother than that in the first bending area 1BA. Accordingly, thetension stress applied to components of the display apparatus in thesecond bending area 2BA in which the bending is smoother may be smallerthan the tension stress applied to the components in the first bendingarea 1BA. Thus, the first inorganic insulating layer of the displayapparatus according to embodiments described above may include the firstopening or a first groove in the first bending area 1BA, but may becontinuous in at least a portion including the second bending area 2BAin the first area 1A. “At least a portion” is in recognition that thefirst inorganic insulating layer may include contact holes H for anelectrical connection to conductive layers arranged thereon andthereunder in the first area 1A. Contact holes H, etc. may have shapesof a circle, an ellipse, a rectangle, or shapes similar to these, whenseen in a plan view, while the first opening may look like a rectanglewith a high aspect ratio, when seen in the plan view.

A display device may not exist in the first bending area 1BA, but mayexist in the second bending area 2BA which belongs to the first area 1A.Accordingly, an apparatus with at least a portion thereof bent may beimplemented. In addition, when a user looks at a display surface of thedisplay apparatus, the user may be led to think, by bending the displayapparatus in the 2BA, that there is no display in the 2BA and aperipheral area in which a pad, etc. are arranged is narrowed.

Since the chamfered portion CP is present as described above, thesubstrate 100 may be simultaneously bent with the first bending axis1BAX as well as the second bending axis 2BAX crossing therewith ascenters. In this case, the chamfered portion CP may be formed round,without an acute angle, in a portion facing the central portion of thesubstrate 100, as illustrated in FIG. 18 .

When the first bending area 1BA is bent with the first bending axis 1BAXas the center and the second bending area 2BA is bent with the secondbending axis 2BAX as another center, as illustrated in FIG. 18 , a highstress may be applied at a corner CN, facing the central portion of thesubstrate 100, of the chamfered portion CP, and the substrate 100, etc.may be torn off or damaged. Accordingly, to reduce or prevent anoccurrence of such defects, the chamfered portion CP may be rounded,without an acute angle, at the corner CN facing the central portion ofthe substrate 100, as illustrated in FIG. 19 . In this case, the radiusof curvature at the corner CN, facing the central portion of thesubstrate 100, of the CP may be approximately about 1/20 to about ⅕ ofthe radius of curvature of the first bending area 1BA, e.g., about 1/10.

In addition, when the first bending area 1BA is bent with the firstbending axis 1BAX as the center and the 2BA is bent with the secondbending axis 2BAX as another center, the edge of the first bending area1BA in the direction of first area 1A may be arranged more toward theedge of the substrate 100 than an extended line of a first cutting line1CL of the chamfered portion CP as illustrated in FIG. 19 , to prevent alarge stress from being applied to the corner CN, facing the centralportion of the substrate 100, of the chamfered portion CP. For example,a separation s1 between the edge of the first bending area 1BA in thedirection of the first area 1A and the extended line of the firstcutting line 1CL may be approximately about 500 μm.

An edge of the second bending area 2BA in the central direction of thesubstrate 100 also may be arranged more toward the edge of the substrate100 than the extended line of a second cutting line 2CL. In this case,since the radius of curvature R2 in the second bending area 2BA isgreater than the radius of curvature R1 in the first bending area 1BA asdescribed above, a magnitude of the stress applied to the corner CN ofthe chamfered portion CP in the second bending area 2BA by the bendingmay be smaller than the corner CN of the chamfered portion CP in thefirst bending area 1BA. Accordingly, a separation s2 between the edge inthe central direction of the substrate 100 in the second bending area2BA and the extended line of the second cutting line 2CL may be shorterthan the separation s1.

Descriptions on the corner CN of the chamfered portion CP may be appliedto embodiments or subsequent various modifications thereof describedabove or below.

The display apparatus is illustrated to include the 2BA only in additionto the first bending area 1BA in FIG. 18 ; however, embodiments are notlimited thereto. For example, as illustrated in FIG. 20 , which is aperspective view of a portion of the display apparatus according toanother embodiment, the display apparatus may include a third bendingarea 3BA and/or a fourth bending area 4BA in addition to the firstbending area 1BA and the second bending area 2BA. In this case, all offour corners may be bent in a display apparatus including four corners.The third bending area 3BA and the fourth bending area 4BA may includeconfigurations the same as or similar to the second bending area 2BA.

Display devices may be arranged in the second bending area 2BA, thethird bending area 3BA, and the fourth bending area 4BA, which belong tothe first area 1A. Accordingly, a display apparatus with all edges bentmay be implemented. In addition, when the user looks at a displaysurface of the display apparatus, the user may be led to think, bybending the display apparatus in the second bending area 2BA through thefourth bending area 4BA, that there is no display in the second bendingarea 2BA through the fourth bending area 4BA and peripheral areas inwhich a pad, etc. are arranged are narrowed.

Unlike as illustrated in FIG. 20 , the first bending area 1BA and thesecond area 2A may be arranged not only in the second direction (the +xdirection) but also in an opposite direction (the −x direction), asillustrated in FIG. 21 which is a perspective view of a portion of thedisplay apparatus according to another embodiment. Various electronicdevices may be arranged in the second area 2A in the opposite direction(the −x direction) of the second direction (the +x direction) like inthe second area 2A in the second direction (the +x direction), or theprinted circuit board, etc. may be electrically connected in thecorresponding area.

By way of summation and review, one or more embodiments provide abendable display apparatus that may have a long usage life, whilesignificantly reducing defect occurrences such as a broken wire duringthe manufacturing process. However, areas of improvement are exemplaryonly and embodiments are not limited thereto.

Example embodiments have been disclosed herein, and although specificterms are employed, they are used and are to be interpreted in a genericand descriptive sense only and not for purpose of limitation. In someinstances, as would be apparent to one of ordinary skill in the art asof the filing of the present application, features, characteristics,and/or elements described in connection with a particular embodiment maybe used singly or in combination with features, characteristics, and/orelements described in connection with other embodiments unless otherwisespecifically indicated. Accordingly, it will be understood by those ofskill in the art that various changes in form and details may be madewithout departing from the spirit and scope of the present invention asset forth in the following claims.

What is claimed is:
 1. A display device, comprising: a substrate; afirst inorganic insulating layer disposed over the substrate and havinga first opening or groove; a first conductive layer on the firstinorganic insulating layer; a second inorganic insulating layer having aplurality of contact holes and a second opening or groove on the firstconductive layer; a first organic material layer over the first openingor groove and the second opening or groove; a second conductive layer onthe first organic material layer, wherein the second conductive layerextends over the first opening or groove and the second opening orgroove and electrically contacts the first conductive layer through thecontact holes, and the second conductive layer has a plurality of holesat a location directly over the first opening or groove.
 2. The displaydevice of claim 1, wherein the display device is bent at the firstopening or groove.
 3. The display device of claim 2, further comprising:a second organic material layer on the second conductive layer over thefirst opening or groove.
 4. The display device of claim 3, furthercomprising: a thin film transistor arranged over the substrate, whereinthe thin film transistor comprises a semiconductor layer, a sourceelectrode, a drain electrode, and a gate electrode, and wherein thefirst inorganic insulating layer is arranged between the substrate andthe gate electrode.
 5. The display device of claim 4, wherein the secondinorganic insulating layer is arranged over the gate electrode.
 6. Thedisplay device of claim 5, further comprising: an encapsulation layercomprising an inorganic insulating layer and an organic material layer,wherein the encapsulation layer is covering the thin film transistor. 7.The display device of claim 6, wherein the second conductive layerincludes a first surface facing the substrate, a second surface oppositeto the first surface, and the plurality of holes penetrating from thefirst surface to the second surface.
 8. The display device of claim 7,wherein the plurality of holes are arranged in the second conductivelayer at locations corresponding to a portion of the first opening. 9.The display device of claim 2, wherein a width of the second opening orgroove is wider than a width of the first opening or groove.
 10. Thedisplay device of claim 3, further comprising: a third organic materiallayer on the second organic material layer over the first opening orgroove.
 11. The display device of claim 1, wherein each hole ofplurality of holes completely penetrates the second conductive layer ina thickness direction.
 12. The display device of claim 11, wherein eachhole of plurality of holes is fan-shaped.
 13. The display device ofclaim 1, wherein the first organic material layer has a concavo-convextop surface in at least a portion in the first opening or groove. 14.The display device of claim 13, wherein the concavo-convex top surfaceof the first organic material layer includes a plurality of protrusionsformed with respective a number of protrusion axes as centers.
 15. Thedisplay device of claim 13, wherein the second conductive layer has aconcavo-convex top surface in at least a portion in the first opening orgroove.
 16. The display device of claim 1, wherein the second conductivelayer has a concavo-convex top surface in at least a portion in thefirst opening or groove.